TY - CHAP M1 - Book, Section TI - Antibody-Mediated Thrombotic Disorders: Thrombotic Thrombocytopenic Purpura and Heparin-Induced Thrombocytopenia A1 - Lichtman, Marshall A. A1 - Kaushansky, Kenneth A1 - Prchal, Josef T. A1 - Levi, Marcel M. A1 - Burns, Linda J. A1 - Linch, David C. Y1 - 2022 N1 - T2 - Williams Manual of Hematology, 10e AB - Thrombotic microangiopathies are characterized by thrombocytopenia, microangiopathic hemolytic anemia, and microvascular thrombosis, leading to variable injury of the central nervous system, kidney, and other organs.The classic form of thrombotic microangiopathy (ie, thrombotic thrombocytopenic purpura [TTP]) is usually associated with an acquired (autoimmune) deficiency of ADAMTS13, a metalloprotease that cleaves the ultra-large multimers of von Willebrand factor normally produced by endothelial cells but that are hypercoagulable. An inherited form of the loss of ADAMTS13 also occurs, termed Upshaw-Shulman syndrome.Hemolytic uremic syndrome (HUS) refers to the thrombotic microangiopathy that mainly affects the kidney and may be diarrhea-associated (caused by enteric infection with Shiga toxin–producing gram-negative microorganisms) or atypical, often due to abnormalities in the regulation of the complement cascade.Secondary thrombotic microangiopathies occur in association with infections, certain drugs, metastatic cancer, malignant hypertension, or after stem cell transplantation.Heparin-induced thrombocytopenia (HIT) is a significant complication of heparin treatment, associated with mild to moderate thrombocytopenia and a high frequency of both arterial and venous thrombosis. HIT is caused by the formation of anti–heparin/platelet factor-4 antibodies that activate platelets, leukocytes, and endothelial cells. SN - PB - McGraw-Hill Education CY - New York, NY Y2 - 2024/03/28 UR - hemonc.mhmedical.com/content.aspx?aid=1189336872 ER -